Controlling flow of medical fluids

ABSTRACT

Medical pinch valve assemblies, networks, manifolds and related methods, the assemblies comprising two or more pinch valves each of which comprises an actuator, a spring-loaded plunger and a valving arm which collapses an array of channel-contained medical tubing with memory at a selected site to occlude flow of medical fluid across the site. When open, the memory of the tubing and the pressure of the medical fluid opens the previously occluded site to permit flow. Hence, flow of medical fluid from source to destination sites is facilitated. Only the tubing is sterilized and tubing removal and replacement is rapidly achieved so that &#39;&#39;&#39;&#39;down time&#39;&#39;&#39;&#39; is virtually non-existent.

United States Patent 1191 Davis July 16, 1974 541 CONTROLLING FLOW or MEDICAL 3,582,284 6/1971 Hamshere et a1 251/5 x FLUIDS 3,599,525 8/1971 Klann ..251/5x Inventor: William P. Davis, Salt Lake City,

Utah

Assignee: Med-Lab Computer Services, lnc.,

Salt Lake City, Utah Filed: May 25, 1973 Appl. No.: 364,184

U.S.'Cl 137/15, 137/6l2.1, 137/315,

251/5, 251/14, 25l/61.4 Int. Cl. F16k 31/145 References Cited UNITED STATES PATENTS Leroy 251/5 10/1972 Kane et al 251/5 Primary Examiner-l-lenry T. Klinksiek Attorney, Agent, or FirmLynn G. Foster 57 ABSTRACT Hence, flow of medical fluid from source to destination sites is facilitated. Only the tubing is sterilized and tubing removal and replacement is rapidly achieved so that down time is virtually non-existent.

13 Claims, 7 Drawing Figures BACKGROUND 1. Field of Invention The present invention relates generally to flow control of medical fluids andmore particularly to a novel pinch valve assembly and manifold for selectively controlling flow of medical fluid, together with related methods.

2. Prior Art In the past, medical valves and valve networks have been unduly expensive. Complete and repeated sterilization has been needed to assure absence of contamination, often because medical fluid was allowed to come in contact with the valve itself. Fluid flow has been difficult to ascertain. Occasionally ports, seals or sliding members of prior art valves and valve networks have tended to clog, damage or entrap fluid or permit leakage. Selective fluid flow control has been less than precise and substantial amounts of time have been lost while a given used valve network was being conditioned for subsequent utilization.

BRIEF SUMMARY AND OBJECTS OF THE PRESENT INVENTION The present invention provides an economical novel medical pinch valve assembly or manifold, together with related methods,the assembly comprising a nonsterile body having grooves or channels receiving sterile tubing in a readily removable fashion. One or more actuators in selected locations are selectively controlled to occlude or not occlude the tubing at one or more predetermined sites to control flow of medical fluid from source to destination sites. Used tubing can be speedily removed and replaced by additional sterile tubing of like type and configuration without need for sterilizing the assembly per se. Fluid flowis easily determined, no fluid contact with valve parts occurs and seals are not required. Fluid damage and entrapment does not occur. r

With the foregoing in mind, it is a primary object of the present invention to provide a novel medical pinch valve assembly or manifold and related methods.

It is a further object of considerable importance to provide a medical pinch valve assembly for selectively controlling fluid flow between source and destination sites which is economical and which accommodates prompt exchange of sterile tubing without the necessity of sterilization of the valve per se.

It is another paramount object of the present invention to provide a novel medical pinch valve manifold which selectively controls the flow of medical fluid, which flow is'visible at all times.

It is an additional object of the present invention to provide a novel medical pinch valve .manifold and method for accommodating selective displacement of the medical fluid without causing the fluid to contact valve components and which does not damage or entrap the medical fluid or permit leakage thereof.

These and other objects and features of the present invention will be apparent from the following detailed description, taken with thereference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side cross-sectional view of a presently preferred medical pinch valve of assembled components in its normally closed condition;

FIG. 2 is a side cross-sectional view of the medical pinch valve assembly of FIG. 1 in its actuated, open condition;

FIG. 3 is a cross-sectional view of a second presently preferred medical pinch valve assembly embodiment according to the present invention;

FIG. 4 is a top plan view of a pinch valve manifold embodying three pinch valve assemblies shown in oper- DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS Specific reference is now made to the drawings, wherein like numerals are used to designate like parts throughout. FIG. 1 illustrates one presently preferred pinch valve, generally designated 10, according to the present invention. The medical pinch valve 10 comprises a main body portion 12 and a pneumatic influent body portion 14. The body portion 14 comprises a male projection 16 having a linear passageway or actuating port 18 concentric with the axis of the medical pinch valve 10. The male projection 16 comprises external serrations 20, adapted to receive a flexible pneumatic tube wherebyair under pressure is delivered to and exhausted from the valve 10.

Interposed'between the main body portion 12 and the end body portion 14 is a diaphragm 22, the periphery 24 which is rigidly held in sealed relation between the portions 12 and 14 The central portion of the diaphragm 22 is permitted to flex within a counterbore recess 26 located at the base of thebody portion 12. Counter bore 26 merges with intermediate counterbore 28 and intermediate counterbore 28 in turn with axial bore 30 of the body portion 12. A valve stem or plunger 32 is movably retained in sealed relation within the bore 30 so that it may appropriately axially reciprocate upon pneumatic command any may be manually rotated by use of knurled exposed end 34.

' A transverse arm 36 is rigidly secured to the stem 32 at location 38 so that at all times the arm 36 moves with the stem 32. In all circumstances, the arm 36 is exposed above thebody portion 12. In a normally closed position of FIG. 1, the arm rests upon the base surface 40 of a surface slot 42. In the actuated open" position of FIG. 2 the arm is elevated completely out of the slot 42 away from the base 40 thereof.

The stem at its interior concealed end 44 is attached to a concentric disc 46, the bottom surface of which is bonded or otherwise caused to adhere to the top surface of the diaphragm 22. Thus, the disc 46 and the diaphragm 22 move together.

A return spring 50 abuts against the shoulder 52 of v the. intermediate counterbore 28 and against the top surface of the disc 46 exerting sufficient force so as, in

the absence of pneumatic pressure on the underside of in the down, closed position shown in FIG. 1.

The body portion 12 at its top surface is covered by cover plate 56. The cover plate 56 is appropriately secured to the body 12 by screws or the like, not shown, so that the plate 56 may be removed as desired. A slot 58 extending through the entire thickness of the plate 56 accommodates axial reciprocation of the arm 36 as the stem 32 moves between the positions of FIGS. 1 and 2, but at the same time prhibits, in the illustrated embodiment under consideration, rotation of the arm 36. When the plate 56 is removed, the user may grip the knurled end 34 and rotate the arm 36 out of superposition over the slot 42. The need for a cover plate is eliminated if the stern travel from the closed to the open position is less than the depth of slot 42, thereby inherently preventing rotation of the stem 32.

A channel or open groove 60 exists in the top surface of the body portion 12 and extends transverse of the slot 42, crossing the slot 42 about midway along its length. A flexible pliable medical tubing 62, having memory and a diameter approximately twice the depth of the slot 60, rests in the slot 60 along the bottom or base thereof. Preferably, the plate 56 and the tubing 62 are transparent so that one may readily observe the flow of medical fluid along the tubing 62.

Ascan be observed from FIGS. 1 and 2, the arm when in the normally closed position compresses the tube 62 so as to fully occlude the same, but at the time does not crush or cause structural damage to the tube. In the open position of FIG. 2, the tubing 62 is shown as being fully open to accommodatefluid flow, the tube being displaced from the occluded to the open condition due to the memory of the material comprising the tubing 62 and pressure of the fluid in the tubing.

It is intended that the valve 10, with the exception of the tubing 62 be nonsterile. Initially, the tubing 62 will be sterile and, following use, may be readily replaced by merely removing the cover plate 56, manually lifting the stem by knurled end 34 and rotating it out of superposition over the tubing 62, removal of the tubing the replacement of the same with new, sterile tubing. When appropriately assembled, air under pressure is introduced from a suitable source through the passage 18 of the portion 14 causing the valve stem 32 and arm 36 to elevate to the position of FIG. 2 therebyselectively passing medical fluid through the tube 62. When pressure from the source is removed, an exhaust mode prevails and the force of spring 50 will evacuate air on the underside of the diaphragm 22 causing the pinched valve to move from the position of FIG. 2 to that of FIG. 1.

Reference is now made to a second presently preferred embodiment of the present invention illustrated in FIG. 3 and generally designated 70. The pinch valve 70 is shown on its side, but it is to be appreciated that it may be oriented in any desired fashion. The portions of the valve 70 which correspond to the valvehave been given identical numerals and no further descrip-' mounting plate. An armature-actuated plunger 80 projects from opening 76 into counterbore 28' of the valve body 12. The plunger 80 .contiguously engages the bottom surface 82 of a bearing plate 84 at the distal end 86. The abutment plate 84 forms an integral part of the valve stem 32'. The upper surface 88 of the plate 84 is engaged by return spring 90, which also engages and bears against shoulder 52' of counterbore 28. The operation of the embodiment of FIG. 3 is fundamentally the same as the operation of the embodiment of FIGS. 1 and 2, pinch valve 70 being illustrated in its non-actuated position (normally closed) in FIG. 3. Thus, when the solenoid 74 is energized, the plugner is extended, thereby displacing the stem 32 to the right and opening the medical tubing 62 for flow of medical fluid from a source to a destination site.

Reference is now made to FIGS. 4 and 5 which illustate an array of pinch valves of the type illustrated and described in connection with FIGS. 1 and 2 and/or FIG. 3. While either valve 10 or 70 could be used, for simplicity FIGS. 4 and 5 will be described in connection with valves 10. It is intended that FIGS. 4 and 5 illustrate generally how the pinch valves according to the present invention may be assembled into arrays. Obviously, many more than three valves could be used depending upon the particular type of medical fluid flow control desired. In the FIGS. 4 and 5 three pinch valves 10 are illustrated having a single one-piece cover plate 56 extending over all three as illustrated in the assembled condition of FIG. 4. Screws 80 may be used to removably hold the cover plate 56 to the three valves 10. The valves 10 comprise surface grooves 60 arranged in a T configuration, when considered as a whole. A T- shaped array of medical tubing 62' comprising branches 82, 84 and 86. Said array of tubing is disposed in the mentioned grooves 60 beneath the cover plate 56'. Each valve 10 is normally closed (see FIG. 1) and, therefore, it can be appreciated by reference'to FIG. 4 that all of the valves may be off at any particular time thereby preventing flow of the medical fluid in any of the branches 82, 84 and 86. By the same token, the selective actuation of the plungers or stems 32 of the three valves 10 can be used to permit flow of medical fluid between any one branch to any other branch.

Again, the present invention has as an objective the provision of valve structure which does not require sterilization. Therefore, it is contemplated that only tubing 62' would be initially sterile and the valves 10 would not be subjected to sterilization processes. Thus, when the tubing 62 has been used and is no longer appropriate for continued use, the cover plate 56' is removed by removal of screws 80. When the cover plate 56' is removed, the valves 10 are exposed as illustrated in FIG. 5, following which the tubing 62 is readily pulled from the grooves 60 and replaced by like tubing.

It should be appreciated that'other configurations in the form of valve assemblies or arrays may be constructed using two or more medical pinch valves in ac cordance with the present invention. In this way, closed valve network embodiment of FIGS. 6 and 7 will now be described. The valve network or manifold, generally designated 110 comprises a one-piece valve body 112. Three stepped bores 130, configurated as are stepped bores 30 of FIGS. 1 and 2, are placed in appropriate cations so as to extend parallel to the depth of the valve body 112. The illustrated top surface of the valve body 112 contains U-shaped grooves or channels 160, each having a base. Said grooves are shaped and located as groove 42 of .FIGS. 1 and 2. Three slots 142 extend transversely across the adjacent groove 160 and open into the adjacent stepped bore 130 as illustrated. In the same fashion as described in connection with FIGS. 1 and 2 the channel 160 is deeper into body 112 than the associated transverse slot 142 by a distance equal to approximately the radius of the transparent medical tubing 162 which is placed in the T-shaped groove .160. As can be observed, the medical tubing 162 is T-shaped also. The described depth difference between grooves 160 and slots 142 prevents damage to the tubing 162 when engaged by the arms 136 of the pinch valve network 110. Each arm 136, in a manner previously described, is anchored nonrotatably to the associated plunger or stem 132. Each stem 132 fits snugly but displaceably within the smallest diameter portion of the stepped bore 130. Each stem is biased as earlier described by a spring 150, which abuts a shoulder of the stepped'bore 130 anda disc 146, secured by a screw 147 to a threaded bore at the lower surface of the associated stem 132. A diaphragm 122 covers the enlarged, bottom opening of each stepped bore 130 and is sealed to the underside of valve body 112 by an end cap 14, identical to the end cap 14 of FIGS. 1 and 2.'Each end cap 14 is secured by cap screws 123 to the underside of body member 112, the screws 126 fitting into threaded blind bores in the body 112.

The array of medical tubing 162 and the grooves 160 at the top surface of the valve body 112 are covered by one-piece transparent plate 156. The plate 156 is secured by countersunk screws 157 to the body member 112 at threaded blind'bores therein disposed in the top surface. Three key-hole openings 136 in the plate 156 accommodate reciprocation of the plungers 132 while preventing rotation of the same. Removal of the cover plate 156 accommodates lifting and rotation of the plungers 132 whereby the array of medical tubing 162, following use, may be removedand replaced by a like array of tubing in sterile condition. Hence, sterilization of the network 110, exclusive of the tubing, is avoided.

. meaning and range of equivalency of the claimsare therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

l. A pinch valve assembly for controlling'the flow of 6 a sterile disposable pliable tube of synthetic material having memory disposed at least in part in the said surface groove;

a non-sterile stem;

means mounting the stem within said body for (a) lineal reciprocation between extended and retracted positions and (b) rotational displacement between functional and nonfunctional positions;

means normally biasing the stem into one of said two lineal positions;

force-applying means displacing the stem into the other of said two lineal positions counter to said bias;

an arm carried by the stem and juxtaposed the groove when the stem is in the functional rotational position such that the arm pinches the tube closed against the body groove to prevent fluid flow through the tube when the stem is in afirst of said two lineal positions, and the arm releases the tube to accommodate the flow of medical fluid through the tube when in the second of said two lineal positions;

means rotataionally displacingthe stem and arm to the nonfunctional rotational position whereby the tube, after it becomes contaminated, may be read ily removed from the groove and replaced in the groove by another sterile tube, following which the stem and arm are returned to their functional rotational position.

2. The assembly of claim 1 further comprising a removable cover plate substantially covering the groove and having a slot adjacent the arm to accommodate said lineal reciprocation.

3. The assembly of claim 1 wherein said biasing means comprise a force-applying spring.

4. The assembly of claim 1 wherein said displacing means comprise a fluid driven diaphragm.

' 5. The assembly of claim 1 wherein said displacing means comprise solenoidmeans.

6. A medical flow control assembly comprising:

a non-sterile L-shaped actuator;

a non-sterile body carrying the actuator for lineal reciprocable movement along the axis of one leg of the actuator, said body having an open groove passageway with a base and side edges normal to and juxtaposed the other leg of the actuator;

a length of sterile disposable medical tubing for communicating medical fluid from one site to another site removably located in the passageway, the depth of the base of the groove being substantially less than the diameter of the medical tubing;

non-sterile means normally biasing the other leg of the actuator away from the tubing allowing substantial unimpeded flow of medical fluid between said sites through the open bore of the medical tubing and non-sterile means for displacing the other leg of said actuator counter to said bias against the tubing and the body juxtaposed the side edges of the groove occluding the tubing by flattening without crushing the same a distance equal to the diameter of the tubing less the depth of the groove, whereby flow of medical fluid through the tubing is accommodated and prevented, respectively.

7. A medical flow control manifold comprising;

an array of sterile tubing of biologically inert plastic material having memory, for electively communcating medical fluid between one site and at least two other sites, said array comprising at least one connector whereby one length of tubing from the one site is joined to at least two other lengths of tubing respectively connecting to said other two sites;

body means having an array-of interconnected open surface grooves eachcomprising a base with side walls into which said array of tubing is correspondingly placed in contiguous relation with the base;

a plurality of separate slots in the surface of the body means, each slot comprising a base and intersecting one of said surface grooves but having a depth less than the depth of the intersected groove;

a tube-occluding arm disposed in each slot across the groove and adjacent the branch of tubing in the groove;

an actuating piston connected to each tubeoccluding arm and associated with the body means for limited reciprocation of the connected arm against and away from the baseof the associated slot adjacent branch'of tubing to occlude by flattening without crushing the adjacent tubing or accommodate opening of the tubing respectively thereby respectively preventing and permitting flow of medical fluid in said branch;

a plurality of automated means each associated with the body means and each respectively moving one actuating piston and associated tube-occluding arm between the reciprocable positions thereof whereby flow of medical fluid across the connector between selected sites in the branches of the tubing is facilitated.

8. The manifold of claim 7 wherein said plurality of automated means are normally positioned to cause the associated tube-occluding arm to occlude the adjacent branch of tubing.

9. The manifold of claim 7 further comprising a cover plate positioned over and covering said surface grooves and intersecting slots.

10. A manifold as defined in claim 9 wherein said cover plate comprises elongated openings accommodating reciprocation of each tube-occluding arm.

-a ,ra qam y mromi i ean an array sterile tubing of biologicalfyinert plastic material having memory, for selectively communicating medical fluid, said array comprising at least one connector whereby one length of tubing is joined to at least two other lengths of tubing;

body means having an array of surface grooves each comprising a base into which said array of tubing is correspondingly placed in contiguous relation with the base;

a plurality of slots in the surface of the body means, each slot intersecting one of said surface grooves;

a tube-occluding arm disposed in each slot away from the base of the groove and adjacent the thick branch of tubing in the groove;

an actuating piston connected to each tubeoccluding arm and associated with the body means for limited reciprocation of the connected arm against and away from the adjacent branch of tubing to occlude or accommodate opening of the tubing respectively thereby respectively preventing and permitting flow of medical fluid in said branch;

a plurality of automated means each associated with the body means and each respectively moving one actuating piston and associated tube-occluding arm between the reciprocable positions thereof whereby flow of medical fluid across the connector between selected branches of the tubing is facili tated;

means exposed beyond the body means and connected to each actuating piston for manual displacement of the associated tube-occluding arm from its slot and rotation thereof out of superimposed relation with the adjacent surface groove whereby the disposable tubing, once contaminated, may be readily removed and replaced by a like array of tubing in sterile condition.

12. A method of controlling flow of medical fluid comprising the steps of:

placing disposable sterile tubing in an open surface groove of a non-sterile pinch valve with an eccentrically disposed tube-occluding arm superimposed over the tubing;

actuating the eccentrically disposed tube-occluding arm of the pinch valve between occluding and nonoccluding positions by remote control to selectively pass and prevent passage of medical fluid across the valve from a source site to a destination site;

preventing, at a site remote from the pinch valve,

fluid flow in the tubing across the pinch valve;

positioning the tube-occluding arm out of superimposed contiguous relation withthe tubing;

disconnecting the used tubing in respect to said source and destination sites;

removing the used tubing from the surface groove and discarding the same;

replacing the used tubing withnew sterile tubing in said groove and in connected relation between the source and destination sites without sterilization of the pinch valve returning the tube-occluding arm for displacement between the occluding and non-occluding positions.

13. A method of controlling fluid flow of medical fluid comprising the steps of;

placing an array of disposable sterile tubing comprising interconnected branches in an arrangement of open surface grooves in a non-sterile body;

actuating selected ones of a plurality of tubeoccluding arms, each comprising part of a pinch valve, respectively, between a stop engaging tube flattening but not crushing occluding position and a nonoccluding position by remote control to selectively channel medical fluid from source to destination sites through selected. tube branches;

preventing, at one or more sitesremote from the and pinch valves. 

1. A pinch valve assembly for controlling the flow of medical fluids comprising: a non-sterile body; a groove in the surface of said body; a sterile disposable pliable tube of synthetic material having memory disposed at least in part in the said surface groove; a non-sterile stem; means mounting the stem within said body for (a) lineal reciprocation between extended and retracted positions and (b) rotational displacement between functional and nonfunctional positions; means normally biasing the stem into one of said two lineal positions; force-applying means displacing the stem into the other of said two lineal positions counter to said bias; an arm carried by the stem and juxtaposed the groove when the stem is in the functional rotational position such that the arm pinches the tube closed against the body groove to prevent fluid flow through the tube when the stem is in a first of said two lineal positions, and the arm releases the tube to accommodate the flow of medical fluid through the tube when in the second of said two lineal positions; means rotataionally displacing the stem and arm to the nonfunctional rotational position whereby the tube, after it becomes contaminated, may be readily removed from the groove and replaced in the groove by another sterile tube, following which the stem and arm are returned to their functional rotational position.
 2. The assembly of claim 1 further comprising a removable cover plate substantially covering the groove and having a slot adjacent the arm to accommodate said lineal reciprocation.
 3. The assembly of claim 1 wherein said biasing means comprise a force-applying spring.
 4. The assembly of claim 1 wherein said displacing means comprise a fluid driven diaphragm.
 5. The assembly of claim 1 wherein said displacing means comprise solenoid means.
 6. A medical flow control assembly comprising: a non-sterile L-shaped actuator; a non-sTerile body carrying the actuator for lineal reciprocable movement along the axis of one leg of the actuator, said body having an open groove passageway with a base and side edges normal to and juxtaposed the other leg of the actuator; a length of sterile disposable medical tubing for communicating medical fluid from one site to another site removably located in the passageway, the depth of the base of the groove being substantially less than the diameter of the medical tubing; non-sterile means normally biasing the other leg of the actuator away from the tubing allowing substantial unimpeded flow of medical fluid between said sites through the open bore of the medical tubing and non-sterile means for displacing the other leg of said actuator counter to said bias against the tubing and the body juxtaposed the side edges of the groove occluding the tubing by flattening without crushing the same a distance equal to the diameter of the tubing less the depth of the groove, whereby flow of medical fluid through the tubing is accommodated and prevented, respectively.
 7. A medical flow control manifold comprising; an array of sterile tubing of biologically inert plastic material having memory, for electively communcating medical fluid between one site and at least two other sites, said array comprising at least one connector whereby one length of tubing from the one site is joined to at least two other lengths of tubing respectively connecting to said other two sites; body means having an array of interconnected open surface grooves each comprising a base with side walls into which said array of tubing is correspondingly placed in contiguous relation with the base; a plurality of separate slots in the surface of the body means, each slot comprising a base and intersecting one of said surface grooves but having a depth less than the depth of the intersected groove; a tube-occluding arm disposed in each slot across the groove and adjacent the branch of tubing in the groove; an actuating piston connected to each tube-occluding arm and associated with the body means for limited reciprocation of the connected arm against and away from the base of the associated slot adjacent branch of tubing to occlude by flattening without crushing the adjacent tubing or accommodate opening of the tubing respectively thereby respectively preventing and permitting flow of medical fluid in said branch; a plurality of automated means each associated with the body means and each respectively moving one actuating piston and associated tube-occluding arm between the reciprocable positions thereof whereby flow of medical fluid across the connector between selected sites in the branches of the tubing is facilitated.
 8. The manifold of claim 7 wherein said plurality of automated means are normally positioned to cause the associated tube-occluding arm to occlude the adjacent branch of tubing.
 9. The manifold of claim 7 further comprising a cover plate positioned over and covering said surface grooves and intersecting slots.
 10. A manifold as defined in claim 9 wherein said cover plate comprises elongated openings accommodating reciprocation of each tube-occluding arm.
 11. a medical flow control manifold comprising; an array of sterile tubing of biologically inert plastic material having memory, for selectively communicating medical fluid, said array comprising at least one connector whereby one length of tubing is joined to at least two other lengths of tubing; body means having an array of surface grooves each comprising a base into which said array of tubing is correspondingly placed in contiguous relation with the base; a plurality of slots in the surface of the body means, each slot intersecting one of said surface grooves; a tube-occluding arm disposed in each slot away from the base of the groove and adjacent the thick branch of tubing in the groove; an actuating piston connected to each tube-occluding arm and associated wIth the body means for limited reciprocation of the connected arm against and away from the adjacent branch of tubing to occlude or accommodate opening of the tubing respectively thereby respectively preventing and permitting flow of medical fluid in said branch; a plurality of automated means each associated with the body means and each respectively moving one actuating piston and associated tube-occluding arm between the reciprocable positions thereof whereby flow of medical fluid across the connector between selected branches of the tubing is facilitated; means exposed beyond the body means and connected to each actuating piston for manual displacement of the associated tube-occluding arm from its slot and rotation thereof out of superimposed relation with the adjacent surface groove whereby the disposable tubing, once contaminated, may be readily removed and replaced by a like array of tubing in sterile condition.
 12. A method of controlling flow of medical fluid comprising the steps of: placing disposable sterile tubing in an open surface groove of a non-sterile pinch valve with an eccentrically disposed tube-occluding arm superimposed over the tubing; actuating the eccentrically disposed tube-occluding arm of the pinch valve between occluding and non-occluding positions by remote control to selectively pass and prevent passage of medical fluid across the valve from a source site to a destination site; preventing, at a site remote from the pinch valve, fluid flow in the tubing across the pinch valve; positioning the tube-occluding arm out of superimposed contiguous relation with the tubing; disconnecting the used tubing in respect to said source and destination sites; removing the used tubing from the surface groove and discarding the same; replacing the used tubing with new sterile tubing in said groove and in connected relation between the source and destination sites without sterilization of the pinch valve returning the tube-occluding arm for displacement between the occluding and non-occluding positions.
 13. A method of controlling fluid flow of medical fluid comprising the steps of; placing an array of disposable sterile tubing comprising interconnected branches in an arrangement of open surface grooves in a non-sterile body; actuating selected ones of a plurality of tubeoccluding arms, each comprising part of a pinch valve, respectively, between a stop engaging tube flattening but not crushing occluding position and a non-occluding position by remote control to selectively channel medical fluid from source to destination sites through selected tube branches; preventing, at one or more sites remote from the body, fluid flow in any branch of the tubing; disconnecting the used array of tubing in respect to said source and destination sites; removing the used array of tubing from the arrangement of surface grooves; replacing the used array of tubing with a new array of sterile tubing positioned in said arrangement of grooves and connected between said source and destination sites, without sterilization of the body and pinch valves. 